Thin-Walled Structures最新文献

Mesoscopic simulation study on density gradient metallic foam sandwich panels under hypervelocity impact 超高速冲击下密度梯度金属泡沫夹层板的细观模拟研究

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-29 DOI: 10.1016/j.tws.2024.112762

Qunyi Tang , Qiguang He , Xiaowei Chen

The high stiffness of sandwich panel shield ensures the survival of satellites and spacecrafts, making them extensively utilized in practical aerospace engineering. Metallic foams are exceptionally appropriate for spacecraft debris shields owing to their light weight and superior energy absorption characteristics. The internal mesostructure of a metallic foam plays a crucial role in determining its protective performance. At the mesoscale, the density gradient metallic foam exhibits a greater potential for protection compared to uniform metallic foam under hypervelocity impact. Therefore, this study investigates the behavior of density-gradient foams under hypervelocity impact. By leveraging three-dimensional Voronoi tessellation in conjunction with the background mesh-mapping algorithm, this study constructed mesoscopic finite element models of the layered and continuous-density gradient metallic foam, considering the internal structure of randomness. Subsequently, the Finite Element-Smoothed Particle Hydrodynamics (FE-SPH) adaptive method in LS-DYNA was employed to conduct numerical simulations of the hypervelocity impact. First, the simulation was validated through a comparison with the experiment. Based on the results of the numerical simulations, the characteristics of the debris cloud and the damage within the foam were analyzed. It was determined that the protection mechanism of the density gradient foam sandwich panel under hypervelocity impact involved a coupling effect between the domino and microchannel effects. The different damage characteristics of layered density gradient foam sandwich panels were analyzed. According to this mechanism, foam sandwich panels with different density-gradient configurations were designed and their protective performances were compared to determine the optimal density-gradient configuration to provide valuable insights into the optimal design of protective structures.

夹层板屏蔽板的高刚度是卫星和航天器的生存保障，在实际航天工程中得到广泛应用。金属泡沫由于其重量轻和优越的能量吸收特性，特别适合用于航天器碎片防护。金属泡沫材料的内部细观结构对其防护性能起着至关重要的作用。在中尺度，与均匀金属泡沫相比，密度梯度金属泡沫在超高速冲击下表现出更大的保护潜力。因此，本文研究了密度梯度泡沫在超高速撞击下的行为。本研究利用三维Voronoi镶嵌结合背景网格映射算法，在考虑内部结构随机性的情况下，构建了层状连续密度梯度金属泡沫的细观有限元模型。随后，利用LS-DYNA中的有限元-光滑粒子流体力学（FE-SPH）自适应方法对超高速碰撞进行数值模拟。首先，通过与实验的对比，验证了仿真的正确性。在数值模拟的基础上，分析了碎片云的特征和泡沫内部的损伤。确定了密度梯度泡沫夹层板在超高速冲击下的保护机制是多米诺骨牌效应和微通道效应的耦合作用。分析了层状密度梯度泡沫夹层板的不同损伤特征。根据这一机理，设计了不同密度梯度配置的泡沫夹芯板，并对其防护性能进行了比较，确定了最优密度梯度配置，为防护结构的优化设计提供了有价值的见解。

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引用次数: 0

Experimental and numerical simulation of explosion resistance of composite structure of shallow-buried box steel structure and polyurethane elastomer supports under the action of ground explosion 浅埋箱钢结构与聚氨酯弹性体支架复合结构在地面爆炸作用下的抗爆性能试验与数值模拟

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-27 DOI: 10.1016/j.tws.2024.112751

Hang Xu , Youquan Qin , Weifeng Zhang , Yingxiang Wu , Tainian Chen , Yunke Lu , Xiangyu Xu

The light weight of thin-walled steel structures and their ease of transport and installation have great advantages for protection works that need to be constructed quickly. With the improvement of weapon accuracy and destructive effects, there is an urgent need to improve the resistance of shallow buried steel protection works. However, according to the design concept of traditional protection structures relying on the strength of materials and structural rigidity to resist explosive load, the size of structural components will also increase, and the advantage of rapid construction is seriously reduced. In this study, a composite structure (hereinafter referred to as a composite structure) consisting of a polyurethane elastomer (PUE) set as supports underneath a box steel structure consisting of sandwich plates is proposed to improve the blast resistance of shallow buried box steel structures from ground explosions without increasing the size of the components. Explosive tests and numerical simulations were used to study the blast resistance of the composite structure and its blast resistance mechanism. Other factors affecting the blast resistance of the composite structure, such as the PUE stress-strain relationship and thickness and arrangement of the PUE supports, were also analyzed. The results show that the composite structure is able to generate overall motion and convert part of the explosive energy into kinetic energy of the overall motion of the structure, which is absorbed by the PUE support, thus reducing the structural load and internal force while decreasing deformation and improving the blast resistance performance. While the PUE stress-strain relationship and arrangement of the composite structure have a significant impact on the enhancement of blast resistance, the influence of the thickness of the PUE support is small.

薄壁钢结构重量轻，便于运输和安装，对于需要快速施工的防护工程具有很大的优势。随着武器精度和杀伤效果的提高，迫切需要提高浅埋钢防护工程的抗冲击能力。但是，按照传统的依靠材料强度和结构刚度来抵抗爆炸载荷的防护结构的设计理念，结构构件的尺寸也会增大，快速施工的优势严重降低。为了在不增加构件尺寸的情况下提高浅埋箱钢结构的抗地面爆炸能力，本研究提出在夹芯板箱钢结构下部设置聚氨酯弹性体（PUE）作为支撑的复合结构（以下简称复合结构）。通过爆炸试验和数值模拟研究了复合材料结构的抗爆性能及其抗爆机理。分析了影响复合材料结构抗爆性能的其他因素，如PUE应力-应变关系、PUE支架的厚度和布置。结果表明，复合结构能够产生整体运动，并将部分爆炸能量转化为结构整体运动的动能，被PUE支架吸收，从而在减小结构载荷和内力的同时减小变形，提高抗爆性能。PUE的应力-应变关系和复合结构的布置对增强抗爆性能有显著影响，而PUE支架厚度的影响较小。

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引用次数: 0

Ballistic performance of additive manufacturing metal lattice structures 增材制造金属晶格结构的弹道性能

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-27 DOI: 10.1016/j.tws.2024.112763

Zhihao Xie , Xinqiang Fu , Qin Zhang , Lulu Liu , Xinying Zhu , Yi Ren , Wei Chen

For the purpose of elucidating the destruction and energy absorption mechanisms of lattice structures during ballistic impacts, this study explored the behavior of two additively manufactured metal lattice structures (BCC and BCCZ) under quasi-static/dynamic compression and ballistic impact through experiments and numerical simulations. Both structures exhibited typical stress-strain behaviors during quasi-static compression, with stress plateauing after reaching yield strength and then sharply declining upon failure. The vertical struts in the BCCZ structure resulted in higher yield strength but lower normalized failure strain compared to the BCC structure, especially at higher strain rates. The ballistic limit of the BCC lattice sandwich target plate at 199 m/s and that of the BCCZ lattice sandwich target plate at 195 m/s. At an impact velocity of 207 m/s, the energy absorbed by the BCC lattice structure itself (498 J) was marginally lower than that absorbed by the BCCZ structure (505 J). The BCC structure, characterized by lower stiffness and yield strength but a larger failure strain, absorbed energy primarily through greater deformation during impact. In contrast, the BCCZ structure, with a smaller failure strain, depended on its higher stiffness and yield strength for energy absorption.

为了阐明点阵结构在弹道冲击中的破坏和能量吸收机理，本研究通过实验和数值模拟研究了两种增材制造金属点阵结构（BCC和BCCZ）在准静态/动态压缩和弹道冲击下的行为。两种结构在准静态压缩过程中均表现出典型的应力-应变行为，在达到屈服强度后应力趋于稳定，破坏后应力急剧下降。与BCC结构相比，BCCZ结构中的垂直支板具有更高的屈服强度和更低的归一化破坏应变，特别是在高应变率下。BCC晶格夹层靶板的弹道极限为199 m/s， BCCZ晶格夹层靶板的弹道极限为195 m/s。在207 m/s的冲击速度下，BCC晶格结构自身吸收的能量（498 J）略低于BCCZ结构吸收的能量（505 J）， BCC结构刚度和屈服强度较低，但破坏应变较大，主要通过较大的冲击变形吸收能量。相比之下，BCCZ结构具有较小的破坏应变，依赖于其较高的刚度和屈服强度来吸收能量。

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引用次数: 0

General analytical solution for stress intensity factors of two asymmetrical radial cracks emanating from a single hole in an infinite isotropic plate 无限大各向同性板中单孔产生的两个不对称径向裂纹应力强度因子的一般解析解

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-26 DOI: 10.1016/j.tws.2024.112759

Shengfan Bi, Yong Huang, Hao Wang

Thin-walled perforated structures are widely used in modern industry, where cracks may emanate from the hole edges due to structural loads and manufacturing processes, potentially reducing the reliability of the structure. This paper presents a general solution for stress intensity factors (SIFs) of two asymmetrical radial cracks emanating from a single hole in an infinite isotropic plate, utilizing complex variable theory. Hole shapes, including quasi-square, parabolic, and pentagonal, etc., are considered as instances, and SIFs at crack tips and stress distributions around the hole edge are provided. The analytical solutions are compared with existing literature and finite element method (FEM) results, which confirm the reliability. Under uniaxial tension or pure shear, for quasi-square, parabolic, and pentagonal shapes with equal crack lengths

(a / H = 0 . 5)

, the maximum stress occurs near the geometric vertices. As the crack length increases, the influence of the hole shape diminishes, causing SIF values to approach those of a Griffith crack.

薄壁穿孔结构广泛应用于现代工业，由于结构载荷和制造工艺的影响，孔口边缘可能产生裂缝，从而降低结构的可靠性。本文利用复变理论，给出了无限各向同性板上单孔产生的两个非对称径向裂纹的应力强度因子的一般解。以准正方形、抛物线形、五边形等孔形为例，给出了裂纹尖端的SIFs和孔边周围的应力分布。将解析解与已有文献和有限元计算结果进行了比较，验证了解析解的可靠性。在单轴拉伸或纯剪切作用下，裂纹长度相等的准正方形、抛物线形和五边形（a/H=0.5），最大应力出现在几何顶点附近。随着裂纹长度的增加，孔形的影响减小，使得SIF值接近Griffith裂纹的SIF值。

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引用次数: 0

Inflation of a toroidal membrane within a fluid-filled elastic spherical enclosure 充满流体的弹性球形外壳内环形膜的膨胀

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-26 DOI: 10.1016/j.tws.2024.112729

Satyajit Sahu, Soham Roychowdhury

The present research investigates the growth based inflation model of an inflated toroidal membrane within a fluid-filled environment enclosed by an elastic spherical cavity. This problem statement resembles the growth of toroidal vesicle membranes within biological cells. The toroidal membrane is described by hyperelastic Mooney–Rivlin model with meridional anisotropy. The rise in internal gauge pressure of the torus causes the surrounding incompressible fluid to exert a distributed radial force on the surface of the elastic sphere, resulting in its deformation. With a subsequent gradual increase in gauge pressure, a contact is initiated as the torus indents onto the inner surface of the elastic sphere. The contact condition is assumed to be frictionless, and a variational formulation is adopted for solving the contact problem. The maximum indentation as well as the generated contact stress are found to be higher with a lesser stiffness of the elastic spherical enclosure. As the contact patch grows, the phenomenon of membrane thinning is predominantly observed at the inner equator of the torus. The growth of the contact boundary varies linearly with increasing torus gauge pressure, but non-linearly with the fluid pressure within the spherical enclosure.

本文研究了弹性球腔包围的充液环境中膨胀环形膜的生长膨胀模型。这个问题陈述类似于生物细胞内环形囊泡膜的生长。环形膜采用具有子向各向异性的超弹性Mooney-Rivlin模型来描述。环面内部表压的升高，使周围不可压缩流体对弹性球表面施加分布径向力，造成弹性球变形。随着随后表压的逐渐增加，当环面缩进弹性球的内表面时，接触开始。假定接触条件为无摩擦，采用变分公式求解接触问题。最大压痕和产生的接触应力发现较高的刚度较小的弹性球面外壳。随着接触片的增大，在环面的内赤道处主要观察到薄膜变薄的现象。接触边界的增长随环面表压的增加呈线性变化，但与球壳内流体压力呈非线性变化。

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引用次数: 0

Diffusion bonding of TC4/TB8 titanium alloys with an interlayer by regulating temperature: Microstructure and mechanical performance 调节温度对TC4/TB8钛合金间层扩散连接的影响：组织与力学性能

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-26 DOI: 10.1016/j.tws.2024.112760

Tianle Li , Renhao Wu , Man Jae SaGong , Zaigham Saeed Toor , Hyoung Seop Kim

Diffusion bonding of α+β type TC4 (Ti-6Al-4V) and metastable β type TB8 (Ti-15Mo-2.7Nb-3Al-0.2Si) alloys with interlayer addition was systematically investigated by regulating temperature, revealing the discrepancies in interfacial microstructure and mechanical performance of the joints. Microstructural evolution at the TC4/Ti interfaces and TB8/Ti interfaces can be attributed to atomic interdiffusion and α/β transformation depending on temperature. Additionally, 7 of the 12 α variants that comply with the Burgers orientation relationship with β parents at the transitional layer are identified. The elongation of the bonded samples upon the tensile direction perpendicular to the interfaces becomes decreased compared to that of samples subjected to the tensile direction parallel to the interfaces. The dislocation characteristics and fracture models are analyzed after plastic deformation. This study indicates that a two-step method (first high-temperature and short-duration, then low-temperature and long-duration) can optimize the microstructure and mechanical performance of joints for Ti alloys exposed to high temperatures.

通过调节温度，系统研究了层间添加α+β型TC4 （Ti-6Al-4V）和亚稳型TB8 （Ti-15Mo-2.7Nb-3Al-0.2Si）合金的扩散结合，揭示了界面组织和接头力学性能的差异。TC4/Ti界面和TB8/Ti界面的微观组织演变可归因于原子间扩散和随温度的α/β转变。此外，12个α变体中有7个在过渡层与β亲本符合Burgers取向关系。与平行于界面的拉伸方向相比，在垂直于界面的拉伸方向上，粘结试样的伸长率降低。分析了塑性变形后的位错特征和断裂模式。本研究表明，采用高温短持续时间、低温长持续时间两步法可以优化钛合金高温接头的组织和力学性能。

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引用次数: 0

First-order GBT for tapered regular convex polygonal tubes 锥形正则凸多边形管的一阶GBT

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-26 DOI: 10.1016/j.tws.2024.112735

Rodrigo Gonçalves

This paper presents an accurate and efficient first-order Generalized Beam Theory (GBT) for linearly tapered regular convex polygonal tubes, such as those widely employed in the construction industry. Even though tapered members require a significantly involved formulation, it is shown that it is possible to enforce the standard GBT assumptions exactly, without additional simplifications, a key aspect that (i) is essential for the accuracy and computational performance of the formulation and (ii) allows identifying the deformed configurations pertaining to inextensible deformation. Consequently, very accurate solutions are achieved even for complex cases, such as tubes with a high taper angle and undergoing localized deformation. The GBT deformation modes for the prismatic case are directly used, meaning that the proposed approach for tapered tubes does not require a specific GBT cross-section analysis procedure. All expressions are presented in a straightforward vector–matrix format, for implementation purposes. The excellent performance of the resulting displacement-based beam finite element and the advantages of the GBT modal decomposition features are highlighted through several numerical examples, where results obtained with refined shell finite element models are used for comparison purposes.

本文提出了一种精确有效的一阶广义梁理论（GBT），适用于建筑行业中广泛使用的线性锥形规则凸多边形管。尽管锥形构件需要一个非常复杂的公式，但研究表明，在没有额外简化的情况下，可以准确地执行标准GBT假设，这是一个关键方面，(i)对公式的准确性和计算性能至关重要，（ii）允许识别与不可扩展变形有关的变形配置。因此，即使对于复杂的情况，例如具有高锥度角和经历局部变形的管，也可以获得非常精确的解决方案。直接使用棱柱体情况下的GBT变形模式，这意味着锥形管的建议方法不需要特定的GBT截面分析程序。为了实现目的，所有表达式都以直接的向量矩阵格式呈现。通过几个数值算例，突出了基于位移的梁有限元的优异性能和GBT模态分解特征的优势，其中使用精细化壳有限元模型获得的结果用于比较目的。

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引用次数: 0

Residual compressive behaviour and CFRP strengthening of SRCFST columns after combined damage of fire and lateral impact SRCFST柱在火灾和侧向冲击复合损伤后的残余压缩性能及CFRP加固

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-26 DOI: 10.1016/j.tws.2024.112756

Sun-Hang Ji , Wen-Da Wang , Yan-Li Shi , Long Zheng

Composite structure may be subjected to impact and fire during its service life, and the damaged member face challenges in the performance evaluation and strengthening. This study conducted an experimental and numerical investigation into the residual compressive behaviour of steel-reinforced concrete-filled steel tubular (SRCFST) columns after combined damage of fire and lateral impact. Thirteen damaged specimens under axial loading were tested, with three specimens strengthened with carbon fiber reinforced polymer (CFRP). The failure modes of specimens, residual compressive capacity, deflection distribution, and strain development were discussed. The finite element analysis model on the residual compressive behaviour of damaged SRCFST columns was then developed and calibrated. The full-range analysis on the residual performance of damaged columns was carried out, included the temperature development, distribution of axial load and bending moment, degradation mechanism of bearing capacity, stress development, and effects of fire exposure time. The parameter study was finally conducted to investigate the effects of various factors on the residual compressive performance of damaged SRCFST columns. The results indicated that increasing the fire exposure time and impact height reduces visibly the residual compressive capacity of damaged specimens. As the two damages accumulate, the axial load of each component gradually reduces, while the axial compressive capacity proportion redistributes.

复合材料结构在使用寿命期间可能会受到冲击和火灾的影响，受损构件在性能评估和加固方面面临挑战。本文对钢管混凝土柱在火灾和侧向冲击双重作用下的残余压缩性能进行了试验和数值研究。对13个轴向损伤试件进行了试验，其中3个试件采用碳纤维增强聚合物（CFRP）加固。讨论了试件的破坏模式、残余抗压能力、挠度分布和应变发展情况。建立了钢筋混凝土混凝土损伤柱残余压缩特性有限元分析模型并进行了标定。对受损柱的残余性能进行了全面分析，包括温度发展、轴向荷载和弯矩分布、承载力退化机制、应力发展以及火灾暴露时间的影响。最后进行了参数研究，探讨了各种因素对损伤混凝土混凝土柱残余抗压性能的影响。结果表明，增加火灾暴露时间和冲击高度，损伤试件的残余抗压能力明显降低。随着两种损伤的累积，各构件轴向载荷逐渐减小，轴向抗压能力比例重新分配。

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引用次数: 0

Study on the blast mitigation behavior of metakaolin-based foam geopolymer (MKFG) as tunnel cushioning layer against external blasts 偏高岭土基泡沫地聚合物（MKFG）作为隧道外爆缓冲层的缓震性能研究

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-26 DOI: 10.1016/j.tws.2024.112752

Wenxin Wang , Fangduo Xiao , Hang Zhou , Shikun Chen , Zhen Wang , Yi Liu , Dongming Yan

In this study, the similarity model contact blast test and numerical simulations were carried out to investigate the protective behavior of tunnels with a metakaolin-based foam geopolymer (MKFG) cushioning layer under blast impacts. In contact blast test, Rock-Foam Geopolymer-Concrete Tunnel (RFGCT) structures with various densities (400, 600 and 800 kg/m³) of MKFG were tested against a blast impact of 100 g TNT. In numerical simulations, several parameters covering TNT equivalent as well as density and thickness of cushioning cladding, were comprehensively discussed. Test results show that the attenuation rate of cushioning cladding to the blast wave is enhanced from 34.7 % to 71.0 % with the reduction of the density of MKFG from 800 kg/m³ to 400 kg/m³. Meanwhile, the reflected tensile wave generated by blast wave falls from 1.85 MPa to 0.66 MPa. When the density of MKFG exceeds 600 kg/m³, the cladding exists obvious defects in energy absorption at the bottom of mid-span and free end, which gradually disappear as the TNT equivalent and cushioning thickness increases. Increasing thickness of the MKFG-400 can lead to excessive overall displacement of the tunnel lining. Full-size uncertainty analysis shows that at TNT equivalents of 2000 kg, the thickness of MKFG-800 as cushion is recommended to be 2–3 times that of the lining.

采用相似模型接触爆破试验和数值模拟方法，研究了在爆炸冲击作用下，采用变高岭土泡沫地聚合物（MKFG）缓冲层对隧道的保护作用。在接触爆炸试验中，采用不同密度（400、600和800 kg/m3）的MKFG对岩石-泡沫地聚合物-混凝土隧道（RFGCT）结构进行了100 g TNT爆炸冲击试验。在数值模拟中，对TNT当量、缓冲包层密度和厚度等参数进行了全面讨论。试验结果表明，当MKFG的密度从800 kg/m3降低到400 kg/m3时，缓冲包层对冲击波的衰减率从34.7%提高到71.0%。同时，冲击波产生的反射拉伸波从1.85 MPa下降到0.66 MPa。当MKFG密度超过600 kg/m3时，包层在跨中底部和自由端存在明显的吸能缺陷，随着TNT当量和缓冲厚度的增加，吸能缺陷逐渐消失。增加MKFG-400厚度会导致隧道衬砌整体位移过大。全尺寸不确定度分析表明，在TNT当量为2000 kg时，MKFG-800作为垫层的厚度建议为衬里厚度的2-3倍。

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引用次数: 0

Analysis of warping defect formation mechanisms in hot molding of CF/PEEK thin-wall structures and their influence on mechanical properties CF/PEEK薄壁结构热成型翘曲缺陷形成机理及其对力学性能的影响分析

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-24 DOI: 10.1016/j.tws.2024.112740

Yue Li , Aisha Yang , Yuting Liu , Yu Gao , Jianfeng Zhou , Yan Dong , Shu Zhu

The hot molding of carbon fiber-reinforced polyether ether ketone composites (CF/PEEK) thin-wall structures employs high cooling rates, which cause uneven material shrinkage across different parts and pronounced warping defects. This study fabricated CF/PEEK thin-wall laminates with a thickness of 1.2 mm through die-pressing technology and analyzed the effects of various cooling processes on plate warping. In addition, the study elucidated the formation mechanism of warping defects in CF/PEEK thin-wall structures and plotted a cooling rate curve to determine a strategy for effectively mitigating such defects. Notably, CF/PEEK hot molding warping involves an asynchronous contraction of molecular chains of crystalline polymers, leading to thermal residual stress. This study also investigated the effects of warpage on bending properties and stability. When warpage ranged from 10 to 15 mm, the maximum bending strength deviation along the plane was approximately 150 MPa, indicating that excessive warping substantially reduces bending strength. Moreover, laminates with minor warpage differences exhibited consistent performance stability. Overall, this study provides valuable insights for enhancing the forming quality of CF/PEEK, thereby promoting their application in advanced equipment.

碳纤维增强聚醚醚酮复合材料（CF/PEEK）薄壁结构的热成型采用高冷却速率，导致材料在不同部位收缩不均匀，并出现明显的翘曲缺陷。采用模压工艺制备了厚度为1.2 mm的CF/PEEK薄壁层压板，并分析了不同冷却工艺对板材翘曲的影响。此外，本研究阐明了CF/PEEK薄壁结构翘曲缺陷的形成机理，并绘制了冷却速率曲线，以确定有效缓解此类缺陷的策略。值得注意的是，CF/PEEK热成型翘曲涉及结晶聚合物分子链的异步收缩，导致热残余应力。本研究还探讨了翘曲对弯曲性能和稳定性的影响。当翘曲量为10 ~ 15 mm时，弯曲强度沿平面的最大偏差约为150 MPa，表明翘曲量过大会大大降低弯曲强度。此外，具有较小翘曲差异的层压板表现出一致的性能稳定性。总的来说，本研究为提高CF/PEEK的成形质量，从而促进其在先进设备中的应用提供了有价值的见解。

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引用次数: 0